21211122020111 has 4 divisors (see below), whose sum is σ = 21662422488672. Its totient is φ = 20759821551552.

The previous prime is 21211122020071. The next prime is 21211122020113. The reversal of 21211122020111 is 11102022111212.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21211122020111 - 2⁶ = 21211122020047 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21211122020111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21211122020113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 225650234210 + ... + 225650234303.

It is an arithmetic number, because the mean of its divisors is an integer number (5415605622168).

Almost surely, 2^{21211122020111} is an apocalyptic number.

21211122020111 is a deficient number, since it is larger than the sum of its proper divisors (451300468561).

21211122020111 is an equidigital number, since it uses as much as digits as its factorization.

21211122020111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 451300468560.

The product of its (nonzero) digits is 32, while the sum is 17.

Adding to 21211122020111 its reverse (11102022111212), we get a palindrome (32313144131323).

The spelling of 21211122020111 in words is "twenty-one trillion, two hundred eleven billion, one hundred twenty-two million, twenty thousand, one hundred eleven".